Allyl 6-amino-4-(4-chloro­phen­yl)-5-cyano-2-methyl-4H-pyran-3-carboxyl­ate

Krishnan, G.A.; Mohandas, T.; Kumar, C.U.; Pillai, M.V.; Sakthivel, P.

doi:10.1107/S2414314619003158

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 4| Part 3| March 2019| x190315

https://doi.org/10.1107/S2414314619003158

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Allyl 6-amino-4-(4-chlorophenyl)-5-cyano-2-methyl-4H-pyran-3-carboxylate

G. Anantha Krishnan,^a T. Mohandas,^b C. Udhaya Kumar,^c M. Velayutham Pillai ^c ^* and P. Sakthivel ^d

^aDepartment of Physics, Saranathan College of Engineering, Panjappur, Tiruchirappalli 620 012, Tamilnadu, India, ^bDepartment of Physics, K. Ramakrishnan College of Engineering, Samayapuram, Tiruchirappalli 621 112, Tamilnadu, India, ^cDepartment of Chemistry, School of Advanced Sciences, Kalasalingam Academy of Research and Education (Deemed to be University), Krishnankoil 626 126, Tamil Nadu, India, and ^dDepartment of Physics, Urumu Dhanalakshmi College, Tiruchirappalli, Tamilnadu, India
^*Correspondence e-mail: m.velayuthampillai@klu.ac.in

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 25 September 2018; accepted 5 March 2019; online 29 March 2019)

In the title compound, C₁₇H₁₅ClN₂O₃, the 4H-pyran ring exhibits a shallow-boat conformation and the chlorobenzene ring occupies an axial position. The O-allyl side chain is disordered over two orientations in a 0.585 (14):0.415 (14) ratio. In the crystal, inversion dimers linked by pairs of weak N—H⋯N hydrogen bonds generate R₂²(12) loops and N—H⋯O hydrogen bonds link the dimers into [001] chains.

Keywords: crystal structure; pyran; hydrogen bonds.

CCDC reference: 1901250

Structure description

Pyran derivatives possess various biological properties such as antimicrobial (Aytemir et al., 2003 ) and anti-mycobacterial (Kumar et al., 2007 ) activities. As part of our studies in this area, we now describe the synthesis and structure of the title compound (Fig. 1).

Figure 1
The molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level.

The 4H-pyran ring exhibits a shallow boat conformation with puckering parameters Q = 0.2185 (3) Å, θ = 77.49 (7)° and φ = 170.4 (8)°: atoms O1 and C7 deviate by 0.108 (2) and 0.135 (2) Å, respectively, from the mean plane of the other atoms. The dihedral angle between the phenyl ring and the 4H-pyran ring (all atoms) is 82.43 (14)°.

In the crystal, inversion dimers linked by pairs of weak N2—H2A⋯N1 hydrogen bonds generate $[R_{2}^{2}]$ (12) loops and N2—H2B⋯O2 hydrogen bonds link the dimers into [001] chains (Table 1, Fig. 2).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2A⋯N1ⁱ	0.83 (3)	2.33 (3)	3.126 (4)	160 (2)
N2—H2B⋯O2ⁱⁱ	0.88 (4)	2.05 (3)	2.894 (3)	161 (3)
Symmetry codes: (i) -x, -y, -z-1; (ii) x, y, z-1.

Figure 2
Partial packing diagram for the title compound showing the N—H⋯N and N—H⋯O interactions as dashed lines.

Synthesis and crystallization

A mixture of 4-chlorobenzaldehyde (1.0 mmol), malononitrile (1.0 mmol), allyl 3-oxobutanoate (1.0 mmol) and a few drops of piperidine was stirred magnetically in 30 ml of absolute ethanol at 80°C for 90 min. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was allowed to cool to room temperature and the solvent was evaporated. The solid thus appeared was collected and washed with cold water and recrystallized from ethanol solution to result in colourless blocks of the title compound (yield 84%).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. The atoms of the allyl group (C15 and C16 and attached H atoms) are disordered over two sets of sites in a 0.585 (14):0.415 (14) ratio.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₇H₁₅ClN₂O₃
M_r	330.73
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	9.3609 (6), 20.3984 (16), 8.5280 (7)
β (°)	95.691 (2)
V (Å³)	1620.4 (2)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.25
Crystal size (mm)	0.15 × 0.15 × 0.10

Data collection
Diffractometer	Bruker Kappa APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2008 )
T_min, T_max	0.963, 0.975
No. of measured, independent and observed [I > 2σ(I)] reflections	17502, 2850, 2011
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.048, 0.139, 1.05
No. of reflections	2850
No. of parameters	241
No. of restraints	38
Δρ_max, Δρ_min (e Å⁻³)	0.35, −0.32
Computer programs: APEX2 and SAINT (Bruker, 2008), SHELXS97 and SHELXL97 (Sheldrick, 2008 ) and ORTEP-3 for Windows (Farrugia, 2012 ).

Structural data

CCDC reference: 1901250

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S2414314619003158/hb4264sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314619003158/hb4264Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314619003158/hb4264Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Allyl 6-amino-4-(4-chlorophenyl)-5-cyano-2-methyl-4H-pyran-3-carboxylate top

Crystal data top

C₁₇H₁₅ClN₂O₃	F(000) = 688
M_r = 330.73	D_x = 1.356 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5292 reflections
a = 9.3609 (6) Å	θ = 2.6–24.2°
b = 20.3984 (16) Å	µ = 0.25 mm⁻¹
c = 8.5280 (7) Å	T = 296 K
β = 95.691 (2)°	BLOCK, colourless
V = 1620.4 (2) Å³	0.15 × 0.15 × 0.10 mm
Z = 4

Data collection top

Bruker Kappa APEXII CCD diffractometer	2850 independent reflections
Radiation source: fine-focus sealed tube	2011 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.036
ω and φ scan	θ_max = 25.0°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −11→10
T_min = 0.963, T_max = 0.975	k = −24→24
17502 measured reflections	l = −10→10

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.139	H-atom parameters not defined?
S = 1.05	w = 1/[σ²(F_o²) + (0.0544P)² + 1.3356P] where P = (F_o² + 2F_c²)/3
2850 reflections	(Δ/σ)_max = 0.002
241 parameters	Δρ_max = 0.35 e Å⁻³
38 restraints	Δρ_min = −0.32 e Å⁻³

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All esds are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > 2sigma(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

The hydrogen atoms bound to the C atoms are treated as riding atoms. The H atoms bonded to N were freely refined.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
Cl1	−0.00313 (10)	0.32803 (5)	0.07877 (13)	0.0874 (4)
O1	0.46275 (18)	0.07969 (10)	−0.32817 (19)	0.0440 (6)
O2	0.4430 (2)	0.07085 (12)	0.2207 (2)	0.0600 (8)
O3	0.6401 (2)	0.11435 (10)	0.1389 (2)	0.0516 (7)
N1	−0.0094 (3)	0.00114 (14)	−0.2957 (3)	0.0595 (10)
N2	0.2910 (3)	0.04447 (15)	−0.5067 (3)	0.0551 (10)
C1	0.0785 (3)	0.25483 (16)	0.0326 (4)	0.0542 (11)
C2	0.0284 (4)	0.19701 (19)	0.0833 (4)	0.0700 (16)
C3	0.0968 (3)	0.13891 (16)	0.0521 (4)	0.0563 (11)
C4	0.2143 (3)	0.13860 (13)	−0.0331 (3)	0.0357 (8)
C5	0.2604 (3)	0.19807 (15)	−0.0864 (4)	0.0528 (11)
C6	0.1941 (3)	0.25649 (15)	−0.0529 (4)	0.0609 (11)
C7	0.2883 (3)	0.07482 (12)	−0.0704 (3)	0.0344 (8)
C8	0.2411 (3)	0.05042 (12)	−0.2353 (3)	0.0341 (8)
C9	0.3244 (3)	0.05766 (13)	−0.3537 (3)	0.0373 (8)
C10	0.5275 (3)	0.08513 (13)	−0.1753 (3)	0.0381 (8)
C11	0.4502 (3)	0.08235 (12)	−0.0517 (3)	0.0341 (8)
C12	0.1022 (3)	0.02369 (13)	−0.2684 (3)	0.0392 (9)
C13	0.5096 (3)	0.08802 (13)	0.1148 (3)	0.0385 (8)
C14	0.6952 (4)	0.12629 (18)	0.3027 (4)	0.0575 (11)
C15	0.6737 (10)	0.1954 (4)	0.3396 (10)	0.063 (3)	0.585 (14)
C16	0.6009 (11)	0.2171 (7)	0.4480 (10)	0.088 (4)	0.585 (14)
C17	0.6848 (3)	0.09330 (16)	−0.1840 (3)	0.0519 (10)
C15'	0.6098 (16)	0.1800 (5)	0.3735 (17)	0.075 (4)	0.415 (14)
C16'	0.660 (2)	0.2373 (7)	0.391 (3)	0.127 (8)	0.415 (14)
H2B	0.355 (4)	0.0512 (16)	−0.574 (4)	0.062 (10)*
H3	0.06296	0.09957	0.08928	0.0675*
H5	0.33816	0.19901	−0.14630	0.0633*
H6	0.22786	0.29618	−0.08817	0.0728*
H7	0.26255	0.04150	0.00459	0.0413*
H14A	0.79655	0.11562	0.31821	0.0690*	0.585 (14)
H14B	0.64492	0.09880	0.37213	0.0690*	0.585 (14)
H15	0.71649	0.22621	0.27898	0.0751*	0.585 (14)
H16A	0.55631	0.18794	0.51141	0.1052*	0.585 (14)
H16B	0.59278	0.26201	0.46347	0.1052*	0.585 (14)
H17A	0.70457	0.09322	−0.29230	0.0778*
H17B	0.73535	0.05782	−0.12929	0.0778*
H17C	0.71572	0.13413	−0.13593	0.0778*
H2	−0.05207	0.19634	0.13904	0.0840*
H2A	0.207 (3)	0.0344 (14)	−0.538 (3)	0.045 (9)*
H14C	0.812 (9)	0.126 (4)	0.277 (9)	0.0690*	0.415 (14)
H14D	0.681 (8)	0.084 (4)	0.364 (9)	0.0690*	0.415 (14)
H15'	0.51942	0.17057	0.40428	0.0903*	0.415 (14)
H16C	0.75006	0.24702	0.36055	0.1522*	0.415 (14)
H16D	0.60634	0.26982	0.43468	0.1522*	0.415 (14)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0708 (6)	0.0727 (7)	0.1122 (8)	0.0276 (5)	−0.0227 (5)	−0.0415 (6)
O1	0.0404 (10)	0.0636 (13)	0.0290 (10)	−0.0127 (9)	0.0085 (8)	−0.0011 (9)
O2	0.0564 (13)	0.0928 (17)	0.0314 (11)	−0.0153 (11)	0.0075 (9)	0.0024 (10)
O3	0.0510 (12)	0.0656 (14)	0.0369 (11)	−0.0125 (10)	−0.0025 (9)	−0.0035 (9)
N1	0.0499 (15)	0.0711 (19)	0.0576 (17)	−0.0178 (14)	0.0059 (12)	−0.0069 (14)
N2	0.0469 (16)	0.089 (2)	0.0302 (13)	−0.0183 (15)	0.0084 (12)	−0.0110 (13)
C1	0.0465 (18)	0.055 (2)	0.058 (2)	0.0072 (15)	−0.0106 (15)	−0.0197 (16)
C2	0.060 (2)	0.076 (3)	0.079 (3)	0.0079 (19)	0.0318 (19)	−0.016 (2)
C3	0.0572 (19)	0.057 (2)	0.059 (2)	−0.0054 (15)	0.0276 (15)	−0.0046 (15)
C4	0.0351 (14)	0.0424 (15)	0.0298 (13)	−0.0040 (12)	0.0044 (10)	−0.0037 (11)
C5	0.0490 (17)	0.0488 (19)	0.063 (2)	−0.0017 (14)	0.0174 (15)	0.0013 (15)
C6	0.061 (2)	0.0420 (18)	0.078 (2)	−0.0004 (15)	−0.0014 (18)	−0.0006 (16)
C7	0.0378 (14)	0.0384 (15)	0.0277 (13)	−0.0049 (11)	0.0071 (10)	0.0009 (11)
C8	0.0348 (14)	0.0364 (14)	0.0314 (13)	−0.0050 (11)	0.0055 (10)	−0.0017 (11)
C9	0.0365 (14)	0.0428 (16)	0.0328 (14)	−0.0062 (11)	0.0050 (11)	−0.0018 (11)
C10	0.0384 (14)	0.0404 (15)	0.0356 (14)	−0.0042 (12)	0.0045 (11)	0.0006 (12)
C11	0.0374 (14)	0.0347 (14)	0.0305 (13)	−0.0029 (11)	0.0054 (10)	−0.0001 (11)
C12	0.0431 (16)	0.0411 (16)	0.0344 (14)	−0.0042 (12)	0.0085 (12)	−0.0025 (12)
C13	0.0414 (15)	0.0395 (15)	0.0345 (14)	0.0013 (12)	0.0036 (12)	−0.0008 (12)
C14	0.061 (2)	0.066 (2)	0.0419 (17)	−0.0012 (17)	−0.0130 (15)	−0.0092 (15)
C15	0.068 (6)	0.047 (5)	0.071 (5)	−0.002 (4)	−0.006 (4)	−0.009 (4)
C16	0.101 (7)	0.090 (8)	0.072 (5)	0.023 (6)	0.006 (5)	0.001 (5)
C17	0.0387 (16)	0.069 (2)	0.0493 (17)	−0.0069 (14)	0.0110 (13)	−0.0054 (15)
C15'	0.099 (9)	0.063 (7)	0.063 (7)	−0.027 (6)	0.004 (7)	−0.018 (6)
C16'	0.154 (14)	0.074 (10)	0.159 (15)	0.028 (9)	0.049 (11)	0.019 (10)

Geometric parameters (Å, º) top

Cl1—C1	1.740 (3)	C11—C13	1.477 (4)
O1—C9	1.368 (3)	C14—C15	1.463 (9)
O1—C10	1.387 (3)	C14—C15'	1.516 (13)
O2—C13	1.199 (3)	C15—C16	1.281 (13)
O3—C13	1.332 (3)	C15'—C16'	1.263 (19)
O3—C14	1.461 (4)	C2—H2	0.9298
N1—C12	1.144 (4)	C3—H3	0.9299
N2—C9	1.339 (4)	C5—H5	0.9300
N2—H2A	0.83 (3)	C6—H6	0.9299
N2—H2B	0.88 (4)	C7—H7	0.9796
C1—C2	1.356 (5)	C14—H14A	0.9696
C1—C6	1.364 (4)	C14—H14B	0.9705
C2—C3	1.385 (5)	C14—H14C	1.14 (8)
C3—C4	1.377 (4)	C14—H14D	1.02 (8)
C4—C5	1.380 (4)	C15—H15	0.9294
C4—C7	1.522 (4)	C15'—H15'	0.9304
C5—C6	1.386 (4)	C16—H16A	0.9302
C7—C8	1.516 (4)	C16—H16B	0.9297
C7—C11	1.516 (4)	C16'—H16C	0.9278
C8—C12	1.412 (4)	C16'—H16D	0.9318
C8—C9	1.344 (4)	C17—H17A	0.9598
C10—C17	1.491 (4)	C17—H17B	0.9600
C10—C11	1.338 (4)	C17—H17C	0.9602

C9—O1—C10	119.7 (2)	C1—C2—H2	119.95
C13—O3—C14	116.5 (2)	C3—C2—H2	119.93
C9—N2—H2B	120 (2)	C2—C3—H3	119.55
H2A—N2—H2B	121 (3)	C4—C3—H3	119.53
C9—N2—H2A	119.0 (18)	C4—C5—H5	119.11
Cl1—C1—C2	120.0 (3)	C6—C5—H5	119.09
Cl1—C1—C6	119.3 (2)	C1—C6—H6	120.51
C2—C1—C6	120.7 (3)	C5—C6—H6	120.55
C1—C2—C3	120.1 (3)	C4—C7—H7	108.06
C2—C3—C4	120.9 (3)	C8—C7—H7	108.05
C5—C4—C7	121.3 (2)	C11—C7—H7	108.05
C3—C4—C7	121.2 (2)	O3—C14—H14A	109.94
C3—C4—C5	117.5 (3)	O3—C14—H14B	109.91
C4—C5—C6	121.8 (3)	O3—C14—H14C	94 (4)
C1—C6—C5	118.9 (3)	O3—C14—H14D	107 (4)
C4—C7—C8	112.2 (2)	C15—C14—H14A	109.92
C4—C7—C11	111.2 (2)	C15—C14—H14B	109.89
C8—C7—C11	109.1 (2)	H14A—C14—H14B	108.32
C7—C8—C12	119.3 (2)	C15'—C14—H14C	129 (4)
C7—C8—C9	121.6 (2)	C15'—C14—H14D	108 (4)
C9—C8—C12	118.9 (2)	H14C—C14—H14D	106 (6)
O1—C9—N2	110.3 (2)	C14—C15—H15	117.13
O1—C9—C8	121.8 (2)	C16—C15—H15	117.22
N2—C9—C8	127.8 (3)	C16'—C15'—H15'	119.74
C11—C10—C17	131.2 (2)	C14—C15'—H15'	119.53
O1—C10—C17	107.7 (2)	C15—C16—H16B	119.99
O1—C10—C11	121.2 (2)	C15—C16—H16A	120.02
C7—C11—C10	122.3 (2)	H16A—C16—H16B	119.99
C7—C11—C13	112.7 (2)	C15'—C16'—H16C	120.16
C10—C11—C13	124.9 (3)	C15'—C16'—H16D	119.80
N1—C12—C8	179.0 (3)	H16C—C16'—H16D	120.04
O3—C13—C11	115.6 (2)	H17A—C17—H17C	109.49
O2—C13—O3	122.6 (2)	H17B—C17—H17C	109.47
O2—C13—C11	121.8 (3)	C10—C17—H17A	109.47
O3—C14—C15	108.9 (4)	C10—C17—H17B	109.46
O3—C14—C15'	110.6 (6)	C10—C17—H17C	109.46
C14—C15—C16	125.7 (9)	H17A—C17—H17B	109.49
C14—C15'—C16'	120.7 (14)

C9—O1—C10—C17	165.8 (2)	C4—C7—C8—C12	−72.5 (3)
C10—O1—C9—N2	−168.6 (2)	C4—C7—C8—C9	102.8 (3)
C10—O1—C9—C8	10.3 (4)	C11—C7—C8—C12	163.7 (2)
C9—O1—C10—C11	−13.8 (4)	C4—C7—C11—C10	−106.8 (3)
C14—O3—C13—C11	174.3 (2)	C11—C7—C8—C9	−20.9 (3)
C13—O3—C14—C15	−99.1 (5)	C8—C7—C11—C13	−164.1 (2)
C14—O3—C13—O2	−4.6 (4)	C8—C7—C11—C10	17.5 (3)
Cl1—C1—C6—C5	178.7 (3)	C4—C7—C11—C13	71.6 (3)
C2—C1—C6—C5	−0.4 (5)	C12—C8—C9—O1	−176.2 (2)
C6—C1—C2—C3	1.7 (5)	C12—C8—C9—N2	2.5 (4)
Cl1—C1—C2—C3	−177.4 (3)	C7—C8—C9—O1	8.4 (4)
C1—C2—C3—C4	−1.3 (5)	C7—C8—C9—N2	−172.9 (3)
C2—C3—C4—C7	−178.9 (3)	O1—C10—C11—C7	−1.5 (4)
C2—C3—C4—C5	−0.3 (4)	C17—C10—C11—C13	0.8 (5)
C3—C4—C7—C11	−138.7 (3)	C17—C10—C11—C7	178.9 (3)
C5—C4—C7—C11	42.8 (3)	O1—C10—C11—C13	−179.7 (2)
C7—C4—C5—C6	−179.8 (3)	C10—C11—C13—O3	18.1 (4)
C3—C4—C5—C6	1.6 (5)	C7—C11—C13—O2	18.7 (4)
C3—C4—C7—C8	98.8 (3)	C10—C11—C13—O2	−163.0 (3)
C5—C4—C7—C8	−79.7 (3)	C7—C11—C13—O3	−160.2 (2)
C4—C5—C6—C1	−1.3 (5)	O3—C14—C15—C16	121.1 (9)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···N1ⁱ	0.83 (3)	2.33 (3)	3.126 (4)	160 (2)
N2—H2B···O2ⁱⁱ	0.88 (4)	2.05 (3)	2.894 (3)	161 (3)

Symmetry codes: (i) −x, −y, −z−1; (ii) x, y, z−1.

Acknowledgements

TM thanks Dr D. Srinivasan, Principal of K. Ramakrishnan College of Engineering, Trichy for support.

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